topic Re: Offset Alignment Issue in Civil 3D Forum

Offset Alignment Issue

davich787 — Mon, 01 Aug 2022 16:07:17 GMT

Hello - I'm having an issue when creating offset alignments for a corridor, the issue being that only one side is being created and the other fails to offset.

I have never encountered this issue before and wondering if anyone had and what I should be doing to correct this?

Thanks very much.

Re: Offset Alignment Issue

MMcCall402 — Mon, 01 Aug 2022 20:10:08 GMT

Possibly a small geometry issue with the alignment.

Were there any yellow triangle warning messages along the alignment that were turned off?

You could temporarily break it into smaller pieces to narrow down where the issue is.

Re: Offset Alignment Issue

sboon — Tue, 02 Aug 2022 02:10:26 GMT

Try creating an offset alignment that is limited to a simple tangent segment of the master centerline. If that works then use the grips to extend it until you can identify the problem area.

Re: Offset Alignment Issue

fcernst — Tue, 02 Aug 2022 03:03:47 GMT

Typically a couple PI’s too close together.. can calculate the convex offset side but not the other concave side.. so start looking in the concave areas on that side.

Think bowtie issues..

Re: Offset Alignment Issue

davich787 — Tue, 02 Aug 2022 08:28:04 GMT

Hi - Thanks very much for these replies, I really appreciate it.

I used a combination of all the above suggestions to locate the problem area, and it was ultimately a couple of PIs on a concave section that was causing the problem. Got rid of those and it was all good.

Thanks again.

Re: Offset Alignment Issue

fcernst — Wed, 03 Aug 2022 01:01:59 GMT

Good.. it would be good for the software to show the bow tie problems during the Offset Alignment workflow.. @TimYarris

Re: Offset Alignment Issue

TimYarris — Fri, 05 Aug 2022 14:09:14 GMT

Great feedback. Would you folks expect this type of notification to be visible in canvas (as warning glyphs), in editing tables like Panorama and ALP, or all of the above?

Re: Offset Alignment Issue

sboon — Fri, 05 Aug 2022 15:24:22 GMT

In this case the offset alignment would fail to create, so there would be no panorama or editing table to see. The issue is that the command fails with no warning or error message. It would be helpful to see at least a dialog that explained the reason for the failure, and maybe a highlight of the relevant segment on the master centerline.

Re: Offset Alignment Issue

fcernst — Sun, 14 Aug 2022 03:31:17 GMT

Show temporary Glyph vectors demonstrating the bowtie problem(s).